This invention relates to an electro-pneumatic valve. In particular, in a preferred embodiment, this invention is directed to an electro-pneumatic valve card that uses a plurality of electromagnetic coils formed on a printed circuit board.
Electro-pneumatic valves are in widespread use in many applications in which gas streams are selectively controlled by electrical signals. One such application involves the patterning of textile substrates using various fluids. In one specific example, as set forth in U.S. Pat. No. 4,116,626, a substrate is contacted by a marking fluid controlled by an electro-pneumatic valve assembly, is made to contact the substrate at the desired location in accordance with electrically encoded patterning information. This valve assembly is associated with, and controls the flow of, a single stream of patterning fluid. In the apparatus contemplated in this example, multiple streams or jets of fluid, exiting from closely spaced orifices along the length of the manifold or patterning array that extends across the full width of a web of material, are required to achieve patterns having the desired high degree of detail.
One of the problems with precision valves currently marketed is the immense space requirements required when creating intricate patterns such as disclosed in U.S. Pat. No. 3,203,447. The present invention solves this problem in a manner not disclosed in the known prior art.